1. Field of the Invention
The present invention relates to a flat panel display device, and more particularly to a flat panel display device that improves picture quality by compensating a panel defect with electrical data.
2. Discussion of the Related Art
Display devices are very important in the information society as a visual information communicating media. Lately, there have been problems in conventional display devices, such as cathode ray tubes (CRT). For example, a CRT display device has a significantly heavy weight and a bulky volume. Due to these problems, there have been developments in various flat panel display devices that can overcome the limitations of such CRT display devices. Such flat panel displays include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP) and an organic light emitting diode (OLED). Most of these flat panel display devices are put to practical use having significant market share in the display device market.
Flat panel display devices include a display panel for displaying a picture. In these display panels, a mura defect typically can be found as a panel defect during the test process of such display panels. Here, a mura is to be construed as a display spot accompanying brightness differences and chromaticity differences on the display screen. The panel defects are mostly generated in a fabricating process, and typically have a fixed form including a dot, line, belt, circle, and polygon, or an undetermined form in accordance with the cause of their generation. Examples of panel defects having such various forms are shown in FIG. 1 to FIG. 3.
FIG. 1 represents a panel defect having an undetermined form. FIG. 2 represents a panel defect of a vertical belt shape. FIG. 3 represents a panel defect of a fixed form. The vertical belt shaped panel defect in FIG. 2 is generated for reasons including overlapping exposure and differences in the lens number. The dot shaped panel defect in FIG. 3 is mainly generated by impurities. As shown in FIG. 3, such panel defect appears to be darker or brighter than an ambient non-defect area. Further, color difference is made when compared with another non-defect area.
Panel defects can lead to defects of the end products, which ultimately results in low production yield. Further, even if the product with panel defects is successfully shipped as a product, the deterioration of the picture quality due to the panel defect can lower the reliability of the product. Accordingly, various methods have been proposed in order to minimize panel defects. The main approach to minimize a panel defect, according to the related art, was to improve the process technology. However, even with an improved process technology, the panel defect can only be relaxed. The panel defect cannot be completely removed according to an improved process technology, according to the related art.